I have a what I am certain is a Pre-War Diana Model 26 Youth Break Barrel Air Rifle. The unique thing about this rifle is the fact that it has Japanese markings on the left side of the barrel breach. It has a serial number in the low 100's. I think it is a youth model as the entire rifle is only 35.5" or 88cm long. It is .177 Caliber. I'm looking for find out any information I can about it. Was it made in Germany for the Japanese or is it a Japanese copy? What would a possible value be on it, as far as I know it is very rare? Looking for answers and advise.